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Is particle physics dead, dying, or just hard?

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Re: Is particle physics dead, dying, or just hard?

#131

Post by andreareina »

klipt wrote: post #24
bananaflag wrote: post #7

It's basically the opposite situation from 150 years ago. Back then, we thought our theory was more or less complete while having experimental data which disproved it (Michelson-Morley experiment, Mercury perihelion, I am sure there are others). Right now, we know our theories are incomplete (since GR and QFT are incompatible) while having no experimental data which contradicts them.

Doesn't that imply our theories are "good enough" for all practical purposes? If they're impossible to empirically disprove?

The fundamental theories are good enough in that we can't find a counterexample, but they're only useful up to a certain scale before the computational power needed is infeasible. We're still hoping to find higher-level emergent theories to describe larger systems. By analogy, in principle you could use Newton's laws of motion (1685) to predict what a gas in a room is going to do, or how fluid will flow in a pipe, but in practice it's intractable and we prefer to use the higher-level language of fluid mechanics: the ideal gas law, the navier-stokes equations, etc.

Re: Is particle physics dead, dying, or just hard?

#132

Post by incr_me »

threethirtytwo wrote: post #130
tehjoker wrote: post #120

Earlier quoted context omitted.

genetic technology and computing technology have been the biggest drivers for a while. i do think it is remarkable to video call another continent. communication technology is disruptive and revolutionary though it looks like chaos. ai is interesting too if it lives up to the hype even slightly. catching a rocket is very impressive, but its just a lower cost method for earth orbit. it does unlock megaconstellations t…

Yeah none of those are step function changes. Video calling another continent is like a tiny step from TV. Yeah I receive video wirelessly on my tv not that amazed when I can stretch the distance further with a call that has video. Big deal. AI is the step function change. The irony is that it became so pervasive and intertwined with slop people like you forget that what it does now (write all code) was unheard of ju…

A step in which function are you talking about, exactly?

Re: Is particle physics dead, dying, or just hard?

#133

Post by jacquesm »

smnplk wrote: post #44
tasty_freeze wrote: post #15

Here is one fact that seems, to me, pretty convincing that there is another layer underneath what we know. The charge of electrons is -1 and protons +1. It has been experimentally measured out to 12 digits or so to be the same magnitude, just opposite charge. However, there are no theories why this is -- they are simply measured and that is it. It beggars belief that these just happen to be exactly (as far as we can…

There are layers science can not access.

By observing the discrepancies between theories we are accessing those layers. Whether we can access them with instruments is a different matter but with our minds we apparently can.

Re: Is particle physics dead, dying, or just hard?

#134

Post by jacquesm »

tariky wrote: post #115

To my uneducated eye it looks like they are stuck in limbo for 120 years. Nothing practical has been create based on those theories. It is just words and calculations spinning in circles. I wish those people focus on practical real world physics. So we all can enjoy new innovations.

> Nothing practical has been create based on those theories.

Ever used GPS?

A CD player?

A laser?

Semiconductors?

Re: Is particle physics dead, dying, or just hard?

#135

Post by T-A »

Sniffnoy wrote: post #118
bananaflag wrote: post #7

It's basically the opposite situation from 150 years ago. Back then, we thought our theory was more or less complete while having experimental data which disproved it (Michelson-Morley experiment, Mercury perihelion, I am sure there are others). Right now, we know our theories are incomplete (since GR and QFT are incompatible) while having no experimental data which contradicts them.

I wouldn't say that we have no experimental data which contradicts them. Rather, we do have experimental data which contradicts them, but no experimental data that points us in the direction of a solution (and whenever we go looking for the latter, we fail). Consider e.g. neutrino masses. We have plenty of experimental data indicating that neutrinos oscillate and therefore have mass. This poses a problem for the stan…

> the standard model neutrinos can't participate in the Higgs mechanism due to always being left-handed

This again? It's only true if you insist on sticking with the original form of Weinberg's "model of leptons" from 1967 [1], which was written when massless neutrinos were consistent with available experimental data. Adding quark-style (i.e. Dirac) neutrino mass terms to the Standard Model is a trivial exercise. If doing so offends some prejudice of yours that right-handed neutrino can not exist because they have no electric and weak charge (in which case you must really hate photons too, not to mention gravity) you can resort to a Majorana mass term [2] instead.

That question (are neutrinos Dirac or Majorana?) is not a "contradiction", it's an uncertainty caused by how difficult it is to experimentally rule out either option. It is most certainly not "a problem for the standard model".

[1] https://journals.aps.org/prl/pdf/10.1103/PhysRevLett.19.1264

[2] https://en.wikipedia.org/wiki/Majorana_equation#Mass_term

Re: Is particle physics dead, dying, or just hard?

#136

Post by T-A »

atakan_gurkan wrote: post #116
bananaflag wrote: post #7

It's basically the opposite situation from 150 years ago. Back then, we thought our theory was more or less complete while having experimental data which disproved it (Michelson-Morley experiment, Mercury perihelion, I am sure there are others). Right now, we know our theories are incomplete (since GR and QFT are incompatible) while having no experimental data which contradicts them.

I disagree, but maybe only because we are using different definitions. For example, we have neutrino oscillations, this requires neutrino mass, which is not part of the standard model of particle physics. In cosmology, there is "lithium problem" (amongst others), which cannot be explained by Lambda-CDM. We know our physical theories are incomplete not only because our mathematical frameworks (GR & QFT) are incompatib…

> neutrino mass, which is not part of the standard model of particle physics

This is getting tiresome...

https://news.ycombinator.com/item?id=46956197

Re: Is particle physics dead, dying, or just hard?

#137

Post by eucyclos »

Paracompact wrote: post #57
cozzyd wrote: post #38

Earlier quoted context omitted.

Even better, there are the "nightmare" scenarios where dark matter can only interact gravitationally with Standard Model particles.

Personally—and this is where I expect to lose the materialists that I imagine predominate HN—I think we are already in a nightmare scenario with regard to another area: the science of consciousness. The following seem likely to me: (1) Consciousness exists, and is not an illusion that doesn't need explaining (a la Daniel Dennett), nor does it drop out of some magical part of physical theory we've somehow overlooked u…

I think the old theory of the planes of existence has a lot of utility here - if you substitute "the dimensionality at which you're analyzing your dataset" for the hermetic concept of "planes of existence" you get essentially the same thing, at least in lower dimensions like one (matter) or two (energy). Mind, specifically a human mind, would be a four dimensional under the old system, which feels about right. No idea how you'd set up an experiment to test that theory though. It may be completely impossible because experiments only work when they work in all contexts and only matter is ever the same regardless of context.

Re: Is particle physics dead, dying, or just hard?

#138

Post by Dylan16807 »

Paracompact wrote: post #57
cozzyd wrote: post #38

Earlier quoted context omitted.

Even better, there are the "nightmare" scenarios where dark matter can only interact gravitationally with Standard Model particles.

Personally—and this is where I expect to lose the materialists that I imagine predominate HN—I think we are already in a nightmare scenario with regard to another area: the science of consciousness. The following seem likely to me: (1) Consciousness exists, and is not an illusion that doesn't need explaining (a la Daniel Dennett), nor does it drop out of some magical part of physical theory we've somehow overlooked u…

How can consciousness have information about the material world if it doesn't interact with it in any way?

And when your fingers type that you experience qualia, are they bullshitting because your fingers have never actually received any signals from your consciousness in any direct or indirect way?

Re: Is particle physics dead, dying, or just hard?

#139

Post by threethirtytwo »

incr_me wrote: post #132
threethirtytwo wrote: post #130

Earlier quoted context omitted.

Yeah none of those are step function changes. Video calling another continent is like a tiny step from TV. Yeah I receive video wirelessly on my tv not that amazed when I can stretch the distance further with a call that has video. Big deal. AI is the step function change. The irony is that it became so pervasive and intertwined with slop people like you forget that what it does now (write all code) was unheard of ju…

A step in which function are you talking about, exactly?

If you want it stated precisely, the function is human cognitive labor per unit time and cost.

For decades, progress mostly shifted physical constraints or communication bandwidth. Faster chips, better networks, cheaper storage. Those move slopes, not discontinuities. Humans still had to think, reason, design, write, debug. The bottleneck stayed human cognition.

LLMs changed that. Not marginally. Qualitatively.

The input to the function used to be “a human with training.” The output was plans, code, explanations, synthesis. Now the same class of output can be produced on demand, at scale, by a machine, with latency measured in seconds and cost approaching zero. That is a step change in effective cognitive throughput.

This is why “video calling another continent” feels incremental. It reduces friction in moving information between humans. AI reduces or removes the human from parts of the loop entirely.

You can argue about ceilings, reliability, or long term limits. Fine. But the step already happened. Tasks that were categorically human two years ago are now automatable enough to be economically and practically useful.

That is the function. And it jumped.

Re: Is particle physics dead, dying, or just hard?

#140

Post by jemmyw »

Paracompact wrote: post #57
cozzyd wrote: post #38

Earlier quoted context omitted.

Even better, there are the "nightmare" scenarios where dark matter can only interact gravitationally with Standard Model particles.

Personally—and this is where I expect to lose the materialists that I imagine predominate HN—I think we are already in a nightmare scenario with regard to another area: the science of consciousness. The following seem likely to me: (1) Consciousness exists, and is not an illusion that doesn't need explaining (a la Daniel Dennett), nor does it drop out of some magical part of physical theory we've somehow overlooked u…

I don't think any of this is particularly nightmarish. Just because we don't yet know how this complex system arises from another lower level one doesn't make it new physics. There's no evidence of it being new or orthogonal physics.

Imagine trying to figure out what is happening on someone's computer screen with only physical access to their hardware minus the screen, and an MRI scanner. And that's a system we built! We've come exceedingly far with brains and minds considering the tools we have to peer inside.

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